Lots of fixes related to PXE booting ESXi profiles without systems:

* write template files for distros on a full sync
* add all settings variables to dictionary for templating pxe configs
* change img_path to local_img_path when it references the full path
  to the tftp root directory (ie. /var/lib/tftpboot/images) instead
  of what a tftp client would see (ie. /images/...)
* allow template files to be written into the tftp root directory, no
  longer restricting just to /var/www/cobbler/rendered
* minor fix to pxeprofile_esxi template
Normalizing some paths to make sure file writes are safe
Adding bootcfg templates for ESXi 5.0/5.1

To use these, the following line needs to be added to the
--template-files field for the given esxi distro:

For 5.0:
/etc/cobbler/pxe/bootcfg_profile_esxi5.template=$local_img_path/cobbler-boot.cfg
For 5.1:
/etc/cobbler/pxe/bootcfg_profile_esxi51.template=$local_img_path/cobbler-boot.cfg
FEATURE - adding ability to grab templated scripts

* Moved scripts/ directory to bin/, since those are all pre-packaged
  executable scripts and /usr/bin is mainly where they go
* Added new scripts/ directory, which will go into /var/lib/cobbler
  alongside kickstarts and snippets. This contains the first script
  for running preseed late-commands.
* Modified sample.seed to call that script
* Modified a few snippets to make them work better with debian/
  ubuntu when using the new templated script functionality
* Minor fix to init script (config/cobblerd) to not use bash-specific
  language constructs, per pull request #461.